67 C10 V8 Correct Exhaust Manifolds

[J&J67C10]

Hello all, simple question, I hope. What would the correct ram horn exhaust manifolds be for a 1967 C10 with a 327 be? Straight drop or angle drop? When we bought our 67 it had a transplanted 350 in it with a straight drop manifold on the passenger side and an angle drop on the drivers side. I am in the process of installing a new exhaust system and I would like to put the correct drop manifolds on as part of the job. Thanks, JandJ.

[58 Special]

Not an expert but I believe the straight down drop ram horns were for 4WD

[chewychevy67]

Angled for 2wd straight down for 4wd.

[too much stuff]

Originally Posted by chewychevy67

Angled for 2wd straight down for 4wd.

I always thought this also but i have seen a straight and an angled on 2wd before. i don't recall which one was where, but wondering if a manual trans could have had a straight dump on the driver side? Or if one had been changed out at one time.

[J&J67C10]

Thanks for the help so far. I'm on the fence as to how I'm gonna work this. I did some research and it seems either way works. I have a driver side straight dump to use so I'm covered there. I plan on taking the manifolds off to run the plug wires correctly so I'll do some mock up and see which will be the better choice.

[MikeB]

I think 67-68 283-327 would have had straight dumps, because the engines were mounted in the rear location. Even for 2WD.

I learned that when returning some headers that wouldn't clear my 69's motor mounts, because they dumped straight down.

[J&J67C10]

Interesting, the frame mounts on our truck I believe are in the front holes, was that way when we got it. The truck was originally a 292. I'll do some mock up when I get to that point. Plug wire routing is next on the list.

[NGN]

Angled back both side, in both my 67 TWD V8 , one three speed manual one 350 auto.
NGN
Nick

[MikeB]

Check this out: https://www.lmctruck.com/1967-72-che...and-components

Looks like 67 was straight on both sides, but 68 was straight on drivers side, and angled on passenger side. And when you get into 69, it's a function of 2WD or 4WD, because engines were mounted forward in 2WD trucks. All that's assuming LMC is correct.

Enough to make your head explode!

[chewychevy67]

I've had 2 67 2wd and 1 with 283 original and 1 327 original. Both were angled. I'm in Canada so maby it's done differently down there. Never had any 4wds.

[67 twins]

Originally Posted by MikeB

Check this out: https://www.lmctruck.com/1967-72-che...and-components

Looks like 67 was straight on both sides, but 68 was straight on drivers side, and angled on passenger side. And when you get into 69, it's a function of 2WD or 4WD, because engines were mounted forward in 2WD trucks. All that's assuming LMC is correct.

Enough to make your head explode!

Don't ever rely on LMC being correct. I don't know about the rest but 67 2wd are both angled back.

[425HP409]

My original 68 with a 307 was both angled back.

[J&J67C10]

Hopefully get out to the shop this weekend and tie into this project. Dang back has been giving me grief all week. This getting old business isn't for the faint of heart.

[R.O.B.]

My 67 C20 had them angled. And when I bought a set of straight down the middle, it was like 2.5 inches from the crossmember, no way to plumb an exhaust.

Factory 327

[J&J67C10]

Guess I'm not following, Which cross member are you referring to?

[R.O.B.]

The front crossmember, the one that the control arms bolt to.

[lil hoodlum]

I'm not sure on the 67's, but on both of my 1968 C10 and C20 with 327s the exhaust manifolds are angled back.

I too thought that the K10s and K20s were straight down.

[SJLenz1340]

My 67 w/327 has the rear facing exhaust exit as well. I also had the alternator mounting points at #1 cylinder position, good luck trying to find one of those!

[KyleSeal]

My 1967 C10 (283 V8) had angled manifolds. With a cast bracket on the manifold for the alternator.

[Ironhorse]

Since these trucks are going on 55 years plus in age a LOT of things were changed and some even cobbled thru the years by previous owners. I have a set of angled back both RH and LH original GM rams horn exhaust and the website I use says correct for 64-68 283, 307 and 327 two wd trucks. Won't work on my '71 4x4 K10, if interested in them send me a PM and I can get some pics for you.

[damnyankee36]

For what it's worth, the 68 2WD, 327 I'm restoring had angled manifolds. It was mostly unmolested so I feel confident they were the original manifolds.

The customer wanted to keep the rams horn style so we went with an aftermarket 2 1/2" outlet design. Like R.O.B.'s post, they are straight down and in was PITA to custom fit the exhaust to them. There isn't much room to fabricate due to the close proximity to the crossmember.

As MikeB mentioned, if the engine was moved back an inch or so, like the 4WD's, it would have made it much easier.

[J&J67C10]

Hey thanks for the help on this. Yes I believe the correct setup is angled ram horn manifolds for 2wd applications. As I said our truck came with a straight drop on the pass side and an angle drop on the driver side. I am still debating what I will do. Of course I have 3 straight drop driver side manifolds to choose from. My back is still giving me grief and up and down under an old truck is not real great for healing. All in good time.

[Chaparralman1974]

Just to add to this thread, my 67 K20 has center dump manifolds on both sides. Mine is a 327.

Clay

[MikeB]

Originally Posted by J&J67C10

As I said our truck came with a straight drop on the pass side and an angle drop on the driver side.

That makes sense with an engine mounted in the forward position, because the driver's side heads sits farther forward than the passenger side. So the angle is needed to clear the motor mount (or cross member?) -- I forget which. I just remember trying straight ones on my 69 C10 and there was no room for a down pipe on the driver's side. Then again, I was trying to install 2.5" rams horns, which have a much larger body.

[damnyankee36]

Originally Posted by MikeB

That makes sense with an engine mounted in the forward position, because the driver's side heads sits farther forward than the passenger side. So the angle is needed to clear the motor mount (or cross member?) -- I forget which. I just remember trying straight ones on my 69 C10 and there was no room for a down pipe on the driver's side. Then again, I was trying to install 2.5" rams horns, which have a much larger body.

My situation exactly. With these manifolds I had less than 1/4" clearance from the motor mount. I had to splice and cut a bend but to clear the crossmember but it didn't make for a very pretty bend. A bit of an irregular shape.